1. Field of the Invention
This invention is directed to liquid blasting systems; to such blasting systems employing abrasive particulates such as sand with the liquid; and particularly to blasting systems with a plurality of liquid and abrasive inlets or nozzles or liquid/abrasive inlets and with a protective housing or shroud provided with vacuum removal of liquid, abrasives, and blasted materials.
2. Description of the Prior Art
Prior art liquid blasting systems are utilized for the cleaning of parts and materials in a variety of industries and enterprises. Such systems employ liquids under pressures ranging from 500 to 50,000 p.s.i. and liquid velocities from 800 to 1250 feet per second.
A typical prior art system is a single-operator high pressure gun as disclosed in U.S. Pat. No. 3,799,440. Various problems are associated with the structure and use of such guns. Many guns are heavy and cumbersome. During operation a reaction force of as much as 40 pounds must be dealt with by the operator. This can be very tiring.
Often, as described in U.S. Pat. No. 3,802,628 a plurality of individually controlled high pressure blast guns will be connected to the same power source. Each gun requires its own operator. Problems associated with such a multiple-gun hook-up to a single power source are similar to the problems encountered with the use of single guns.
The NLB Spin Jet is a liquid blasting system which employs four liquid nozzles with a housing or body. The nozzle or nozzles are located under the housing where they are connected to a rotating member. There is no vacuum on any part of the device to remove fluid or abrasives. The NLB Corp. expansion joint cleaning system uses another NLB Corp. "Expansion Joint Cleaner" which is similar to the NLB Spin Jet. The NLB apparatuses cannot adequately deal with abrasives.
There has long been a need for a liquid blasting system which has a high production rate, requires only one operator, uses abrasives more effectively, is of simple construction and easy to repair, and which eliminates health and environmental problems related to such systems.